[U-Boot] [PATCH 1/2] i.MX6: nand: extend nandbcb command for imx6UL(L)

[Shyam Saini]

Hi Parthiban,

Thanks a lot for working on this.

Please see comments below.

> Firmware Configuration Block(FCB) for imx6ul(l) needs to be
> BCH encoded. This patch depends on [1].
>
> [1]: https://patchwork.ozlabs.org/project/uboot/list/?series=113810
>
> Signed-off-by: Parthiban Nallathambi <pn at denx.de>
> ---
>  arch/arm/mach-imx/Kconfig       |  1 +
>  arch/arm/mach-imx/cmd_nandbcb.c | 72 ++++++++++++++++++++++++++++++++-
>  2 files changed, 71 insertions(+), 2 deletions(-)
>
> diff --git a/arch/arm/mach-imx/Kconfig b/arch/arm/mach-imx/Kconfig
> index aeb5493488..175bed601e 100644
> --- a/arch/arm/mach-imx/Kconfig
> +++ b/arch/arm/mach-imx/Kconfig
> @@ -74,6 +74,7 @@ config CMD_HDMIDETECT
>  config CMD_NANDBCB
>         bool "i.MX6 NAND Boot Control Block(BCB) command"
>         depends on NAND && CMD_MTDPARTS
> +       select BCH if MX6UL || MX6ULL
>         default y if ARCH_MX6 && NAND_MXS
>         help
>           Unlike normal 'nand write/erase' commands, this command update
> diff --git a/arch/arm/mach-imx/cmd_nandbcb.c b/arch/arm/mach-imx/cmd_nandbcb.c
> index 065b814b2e..34176ee6e4 100644
> --- a/arch/arm/mach-imx/cmd_nandbcb.c
> +++ b/arch/arm/mach-imx/cmd_nandbcb.c
> @@ -14,8 +14,10 @@
>
>  #include <asm/io.h>
>  #include <jffs2/jffs2.h>
> +#include <linux/bch.h>
>  #include <linux/mtd/mtd.h>
>
> +#include <asm/arch/sys_proto.h>
>  #include <asm/mach-imx/imx-nandbcb.h>
>  #include <asm/mach-imx/imximage.cfg>
>  #include <mxs_nand.h>
> @@ -25,6 +27,66 @@
>  #define BF_VAL(v, bf)          (((v) & bf##_MASK) >> bf##_OFFSET)
>  #define GETBIT(v, n)           (((v) >> (n)) & 0x1)
>
> +static uint8_t reverse_bit(uint8_t b)
> +{
> +       b = (b & 0xf0) >> 4 | (b & 0x0f) << 4;
> +       b = (b & 0xcc) >> 2 | (b & 0x33) << 2;
> +       b = (b & 0xaa) >> 1 | (b & 0x55) << 1;
> +
> +       return b;
> +}
> +
> +static void encode_bch_ecc(void *buf, struct fcb_block *fcb, int eccbits)
> +{
> +       int i, j, m = 13;
> +       int blocksize = 128;
> +       int numblocks = 8;
> +       int ecc_buf_size = (m * eccbits + 7) / 8;
> +       struct bch_control *bch = init_bch(m, eccbits, 0);
> +       u8 *ecc_buf = kzalloc(ecc_buf_size, GFP_KERNEL);
> +       u8 *tmp_buf = kzalloc(blocksize * numblocks, GFP_KERNEL);
> +       u8 *psrc, *pdst;
> +
> +       /*
> +        * The blocks here are bit aligned. If eccbits is a multiple of 8,
> +        * we just can copy bytes. Otherwiese we must move the blocks to
> +        * the next free bit position.
> +        */
> +       WARN_ON(eccbits % 8);
> +
> +       memcpy(tmp_buf, fcb, sizeof(*fcb));
> +
> +       for (i = 0; i < numblocks; i++) {
> +               memset(ecc_buf, 0, ecc_buf_size);
> +               psrc = tmp_buf + i * blocksize;
> +               pdst = buf + i * (blocksize + ecc_buf_size);
> +
> +               /* copy data byte aligned to destination buf */
> +               memcpy(pdst, psrc, blocksize);
> +
> +               /*
> +                * imx-kobs use a modified encode_bch which reverse the
> +                * bit order of the data before calculating bch.
> +                * Do this in the buffer and use the bch lib here.
> +                */
> +               for (j = 0; j < blocksize; j++)
> +                       psrc[j] = reverse_bit(psrc[j]);
> +
> +               encode_bch(bch, psrc, blocksize, ecc_buf);
> +
> +               /* reverse ecc bit */
> +               for (j = 0; j < ecc_buf_size; j++)
> +                       ecc_buf[j] = reverse_bit(ecc_buf[j]);
> +
> +               /* Here eccbuf is byte aligned and we can just copy it */
> +               memcpy(pdst + blocksize, ecc_buf, ecc_buf_size);
> +       }
> +
> +       free(ecc_buf);
> +       free(tmp_buf);
> +       free_bch(bch);

I have used kfree() instead of free() in entire nand bcb code
So, I think for consistency reason it should be kfree here.

Could you please resend this patch with above mentioned changes.
Other than this,

>
>  static u8 calculate_parity_13_8(u8 d)
>  {
>         u8 p = 0;
> @@ -231,8 +293,14 @@ static int nandbcb_update(struct mtd_info *mtd, loff_t off, size_t size,
>                 goto dbbt_data_page_err;
>         }
>
> -       memcpy(fcb_raw_page + 12, fcb, sizeof(struct fcb_block));
> -       encode_hamming_13_8(fcb_raw_page + 12, fcb_raw_page + 12 + 512, 512);
> +       if (is_mx6ul() || is_mx6ull()) {
> +               /* 40 bit BCH, for i.MX6UL(L) */
> +               encode_bch_ecc(fcb_raw_page + 32, fcb, 40);
> +       } else {
> +               memcpy(fcb_raw_page + 12, fcb, sizeof(struct fcb_block));
> +               encode_hamming_13_8(fcb_raw_page + 12,
> +                                   fcb_raw_page + 12 + 512, 512);
> +       }
>         /*
>          * Set the first and second byte of OOB data to 0xFF, not 0x00. These
>          * bytes are used as the Manufacturers Bad Block Marker (MBBM). Since

Acked-by: Shyam Saini <shyam.saini at amarulasolutions.com>